The pharmaceutically active compound flupirtine (chemical designation 2-amino-3-carbethoxyamino-6-(4-fluorobenzylamino)-pyridine is an analgesic, i.e., it causes an insensibility to pain without anesthesia or loss of consciousness. The preparation of this compound and of its physiologically acceptable salts is described in German Pat. No. 1,795,858 and in German Pat. No. 3,133,519.